Saturday 1 May 2004 20.17 EDT
First published on Saturday 1 May 2004 20.17 EDT

They are the images I thought I would never have to see again, sickening pictures of Iraqi prisoners, naked, tortured and humiliated. Surely liberation from Saddam Hussein's brutal, evil regime had seen an end to all of that? Yet here they are, photographs of American soldiers abusing prisoners in Iraq's notorious Abu Ghraib's dungeon and of British servicemen brutalising captives in Basra.

They have sent shock waves around the world and shivers down my spine. During the Gulf war in 1991, I was shot down over Iraq, taken prisoner, tortured, humiliated and paraded on TV in pictures that provided an enduring image of that war. Now, perhaps, these horrific new pictures from Iraq will be the lasting image of so-called liberation.

I was held at Abu Ghraib prison during my ordeal as a POW. It was a place of monstrous cruelty and unspeakable brutality; at times the screams of men and women echoed around the bare cell blocks and I would try to bury myself under my single, lice-infested blanket to block out the noise.

On one occasion etched in my memory the guards came crashing into my cell. Blows rained down on me from all sides and I fell to the floor under a merciless avalanche of abuse. I clearly remember watching the blood drip from my nose and form pools in the dust of the cell. At one point a guard pointed a gun at my head and told me he was going to kill me, he pulled the trigger but the hammer fell on an empty barrel; he had removed the bullets as part of his game.

That was all 13 years ago in a different Iraq, and to be honest I expected that sort of treatment, I knew how brutal the regime could be and that I could expect no mercy once in its grasp.

But it is all meant to be over now. Last year America, with Britain at its side, went to war to put an end to such brutality. The Iraqi people are meant to be liberated from a regime that ignores the rules of war, that knows no bounds in its cruel, degrading treatment of prisoners. Which is why these shocking, horrific images of soldiers abusing Iraqi prisoners are almost too evil to comprehend. Naked prisoners are sexually abused while an American female soldier looks on in laughter and palpable pleasure. A British soldier urinates on a man who has been beaten and abused. These are the images I thought I would never see again. The criminal acts of a few bring shame and disgrace to all of the allied forces in Iraq. This is the sort of evil deed perpetrated on myself and the other allied POWs in 1991. We are meant to have rescued the Iraqis from that, we are meant to be above this degradation.

It may be that the abusers are simply a few rotten apples poisoning the whole military barrel and I have no doubt that the vast majority of British and American troops are doing their job as best they can in incredibly trying conditions. But the episode has done untold damage to the allied forces in Iraq and the backlash from the civilian population could be catastrophic.

The military battle to topple Saddam Hussein's evil regime and free the Iraqi people from oppression was won more than a year ago. But these sickening pictures show that there is still a long way to go to win the trust and respect of the Iraqi population.

· John Nichol was a POW during the 1991 Gulf war, and is now a writer and broadcaster. He is co-author, with Tony Rennell, of 'The Last Escape - The Untold Story of Allied POWs 1944-45', published by Penguin.